Hydrogen fluoride is useful notably as feed material for chemical manufacturing processes such as manufacture by electrolysis of molecular fluorine (F2), useful for example as chamber cleaning gas in the semiconductor industry, and the manufacture of other fluorinated chemicals such as fluorinated hydrocarbons.
In reference WO 2004/009873, an apparatus and a method for the generation of fluorine by the electrolysis of hydrogen fluoride are described. The apparatus comprises: a plurality of individual fluorine generating cassettes; said individual fluorine generating cassettes being operably connected to a fluorine gas distribution system for the remote use and consumption of said fluorine gas; said fluorine generating cassettes being individually isolatable from said gas distribution system and removable from the apparatus for remote maintenance. In line 32 on page 24, it is mentioned that a supply of liquid hydrogen fluoride is held in a tank. A hydrogen fluoride vaporizer vaporizes liquid hydrogen fluoride from the tank and supplies it to the cassettes to maintain a constant concentration of electrolyte.